Semiconductor devices are employed in various systems for a wide variety of applications. Device fabrication typically involves a series of process steps including layering material on a semiconductor substrate wafer, patterning and etching one or more of the material layers, doping selected layers and cleaning the wafer.
Semiconductor manufacturers continually seek new ways to improve performance, decrease cost and increase capacity of semiconductor devices. Capacity and cost improvements may be achieved by shrinking device size. For example, in the case of trench capacitors, more and more cells can fit onto the chip by reducing the size of the memory cell components such as capacitors and transistors. The size reduction results in greater memory capacity for the chip. Cost reduction is achieved through economies of scale. Unfortunately, performance can suffer when device component size is reduced. Therefore, it is a challenge to balance performance with other manufacturing constrains.